p1(-1,-4) p2(2,3)
(D2+D-6)y=e2x
12=xcos90
inverse function
1 - x
2x / x - 1
1/x - 3
4 to the power of -2
-x(x^2-41x+85)=0
=(3−λ)(λ^2−9λ+16)−20+4λ
next number in the sequence 16, 8, 12, 21, 37
